With the increase in the spread of infectious diseases, and in particular the risk of infection due to repeated use of hypodermic needles, it is desirable to create a syringe which can be used only a single time. Various syringes exist which allow the user to break off the needle once the syringe has been used. However, until someone chooses to break off the needle of such a syringe, it is possible to reuse the syringe.
Other single dose syringes exist, in particular, the ABBOJECT made by Abbott Laboratories, which employs a vial and an injector. Both the vial and the injector have caps on one of their ends. The vial has a small enough outer diameter that it can fit into the inner diameter of the injector. Once the vial is inserted into the injector and rotated clockwise a specific number of turns, the medication will enter the needle, whereupon the needle cover is removed, and the device is ready for use.
Another single dose device is the TEL-E-JECT device made by the Hoffmann LaRoche Inc. Company. This device employs a plastic plunger which is hollow and fits over a rubber needle cover during transport. The plunger is removed from the rubber needle cover and screwed into a plunger in a plunger barrel containing a dose of a particular drug. Once the plunger is screwed into the piston barrel, the TEL-E-JECT syringe is ready for use.
The aforementioned devices suffer from various drawbacks. In particular, these devices require significant storage space and are complicated to set up. In addition, the TEL-E-JECT device, while providing a single dose in its initial system, can be reused since the plunger screws into the piston, thus allowing the plunger to be pulled back to draw in a second dose of a drug for subsequent delivery.